4. Production and Rollout

Cutover strategy:

• Choose wave-based rollout by department; maintain read-only legacy for 30–60 days.

• Freeze windows agreed with business; feature flags to limit blast radius.

Data migration:

• ETL with validation rules; sampling & reconciliation; dual-write/dual-read if needed; sign-off criteria.

Go-live playbook:

• Roles with on-call schedule; command channel; decision matrix; rollback criteria & steps; comms templates.